Proton Driver / Project X
description
Transcript of Proton Driver / Project X
Proton Driver / Project X
Keith Gollwitzer
Fermilab
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 2
Outline
• Proton Driver Requirements• Project X as part of Proton Driver
– Reference Design– Upgrade Path
• Formatting Rings– Accumulator– Compressor
• Delivery to Target• Plans
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 3
Proton Driver Requirements
• Start from IDS-NF
• Muon Collider is similar except– 1 Bunch per train at 12-15 Hz
August 30, 2012
Parameter Value
Kinetic Energy 5-15 GeV
Average Beam Power 4MW (3.125 x 1015 protons/s)
Repetition Rate 50 Hz
Bunches per train 3
Total Time for bunches 240 μs
Bunch Length (rms) 1-3 ns
Beam Radius (rms) 1.2 mm
Geometric Emittance (rms) < 5 μm
β* at target > 30 cm
Note that 1 bunch is acceptable
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 4
Project X Mission Goals
• Provide a neutrino beam for long baseline neutrino oscillation experiments based on a capability of targeting at least 2 MW on proton beam power at any energy between 60-120 GeV.
• Provide MW-class, multi-GeV, proton beams supporting multiple kaon, muon and neutrino based precision experiments. Simultaneous operations of the rare processes and neutrino programs are required.
• Provide a path toward a muon source for possible future Neutrino Factory and/or Muon Collider.
• Provide Options for implementing a program of Standard Model tests with nuclei and/or nuclear energy applications.
August 30, 2012
Project X
: Accelerator O
verview June 2011
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 5
Project X Reference Design
• CW Linac will support average beam current of 1 mA to 3 GeV
• Pulsed Linac (3-8 GeV) will have a ~5% duty factor
• Possible 8 GeV beam power of 320 kW
• Programmable Chopper System (part of H- source) will provide appropriate bunch structure for the linac experiments as well as fill the appropriate part of the RF buckets in the accumulating Recycler Ring
August 30, 2012
Pulsed Linac chosen over RCS in FY11 as a better upgrade path for MAP
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 6
ChoppersOne gross chopper prior to RFQ
Programmable chopper after RFQ (162.5MHz) which is capable of
single bunch selection; limits beam current in CW linac
Project X Choppers & Splitters
August 30, 2012
SplittersPulsed Dipole: switch from 3GeV experiment area and Pulsed Linac
Transverse RF beam splitter synchronized with programmable
chopper
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 7
Gross Chopping & Splitting
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 8
Fine Chopping
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 9
Project X – MAP Task Force
• Members of Project X and MAP teams have outlined how to – Upgrade Project X to achieve 4MW at 8GeV
• Increase particles– Doubling per linac bunch & average beam current to 5 mA
• Increase pulsed linac duty factor– Increase to 10%
– Beam Reformatting• Accumulation Ring• Bunch Compression
August 30, 2012
Met April 2011- December 2011 Working on report
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 10
Proton Driver Layout
August 30, 2012
Accumulator Ring
Compressor Ring
4MW Target
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 11
Project X Upgrade Path - 1
August 30, 2012
Front End (warm)H- ion source, RFQ, MEBT, Programmable Chopper System
Initially 5mARun at 10mA (Ion source is capable)
Programmable Chopper
Capable of bunch by bunch 162.5MHz
Will suppress beam to limit beam current down stream to
5mA 1mA average
Entire front end is being
designed for 10mA
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 12
Front End Collimation
• Systems designed to intercept beam will have to be able to handle the increased number of particles – Factor of two prior to chopper system– Factor of five downstream of chopper
• Project X team is designing an absorber associated with the programmable chopper capable of 25kW from 5kW
• Will also need to be able to handle increase in beam size– Larger emittance for larger RFQ output current
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 13
Project X Upgrade Path - 2
August 30, 2012
3 GeV CW SRF LinacAverage beam current 1mA 5mA
325 and 650MHz
Retuning of couplers to be efficient –may set initially for higher current
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 14
Project X Upgrade Path - 3
August 30, 2012
Pulsed Linac
1.3 GHz SRF3-8 GeV
10% 5% duty factor at 10Hz 15Hz
More RF powerUpgrade of couplersMore cryo capacity
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 15
Project X Pulsed Linac
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 16
Project X Upgrade Path - 4
August 30, 2012
• Conventional facilities– More water cooling– Building space
• More cryo capacity• More Klystrons
• An upgrade re-uses >75% of RDR cost
Project X RDR cost distribution (FY11)
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 17
Project X to Formatting Rings
• The outlined Project X upgrade will provide
4MW of H- beam at 8GeV – Pulsed linac repetition rate is appropriate for
NF/MC– Linac beam pulses are delivered at 162.5MHz with
only 50% occupancy
• Beam re-formatting– Accumulation/conversion to proton beam– Package in few bunches of appropriate length
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 18
Possible Operational Schemes
• Upgraded Project X pulses at 15Hz– Programmable chopper allows half of beam to be sent
into RF bucket for 6.67ms pulse
• Accumulation Ring is used to convert to proton beam into 4 bunches
• Transfer beam to Compressor Ring– Neutrino Factory: 1 bunch at a time (effectively 60Hz)– Muon Collider: all bunches at once
• Compressor Ring bunch rotates beam and extracts– Muon Collider: each bunch takes different path to
arrive at target simultaneouslyAugust 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 19
First passes at Rings’ Designs
• Several people have designed and investigated rings
August 30, 2012
Parameter Accumulator CompressorCircumference 300m 300mTransition γt 4.0 11.3Slip factor αp =1/γt2-1/γ2 0.051 -0.0032rf voltage Vrf 4.0kV 120kV bunches (h) 4 4
Parameter Symbol Value Unit
Circumference C 292 m
FODO cells L, NC, φ 11.2, 20, 90 m
Dipole params L, B 4.0, 1.25 m, T
Quad params L, B’ 0.8, 8.0 m, T/m
βmax,ηmax βmax,ηmax 18.0, 3.5 m
transitions αp, γt0.038, 4.52
tunes νx, νy 5.44, 5.30
rf voltage Vrf, frf 4kV, 4MHz
Parameter AR CRCircumference, m 308.23 308.23 Momentum compaction -0.052 0.001Slippage factor -0.063 -0.01RF frequency, MHz 3.87 3.87RF voltage, kV 10 240Synchrotron tune 2.110-4 4.210-4
Peak current, A 100 1040Final r.m.s. bunch length, ns 29.2 3.2Final r.m.s. energy spread 5.210-4 6.910-3
Threshold impedance, Ohm 20 3 53R.m.s. emittance, m 5 5Space charge tuneshift, h/v (Gaussian distribution) 0.02/0.02 0.14/0.16Betatron tunes, h/v 7.94/6.91 6.76/8.44
Will continue to develop and investigate lattices
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 20
Accumulator Injection R&D
• Stripping 4MW at 8GeV – Foils versus laser
• Will interface with other groups also doing high-powered multi-GeV stripping
• Need to develop method to handle ~1% of beam not stripped
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 21
Compressor Ring
• Accept single bunch, or all bunches, from Accumulator• Does a quick bunch rotation• Extracts beam
• Do not expect space charge problem due to quick process
• Investigate location– Can be away from Project X and Accumulator – Could be in same tunnel as Accumulator– Possibly be incorporated into Accumulator
• NF issue would be multiple bunch rotations may blow-up beam
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 22
Neutrino Factory Beam Line
• Extracted beam from Compressor Ring is delivered to target
• Beam enters the target area with an angle to the solenoid axis and will have a path such that the center of the interaction region is on the solenoid’s axis
• Discussions with target station group about where last focusing element can be placed– Target Infrastructure
• Jet• Cooling
– Radiation ShieldingAugust 30, 2012
From Target and Absorbers talk by K. McDonald
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 23
Muon Collider Beam Line - 1
• Extracted bunches from Compressor Ring are sent into different length beam lines
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 24
Muon Collider Beam Line - 2
• Each beam line enters the target area with an angle to the solenoid axis and will have a path such that the center of the interaction region is on the solenoid’s axis
August 30, 2012
Simplified schematic with no solenoid field
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 25
Muon Collider Beam Line - 3
• Once we understand the Neutrino Factory single beam line and target area interface:– Will determine which 4 beam paths into target
area can be used– Determine spacing of beams for last beam line
element which will have to do the following• Be part of the final focus for all beams• Be a 4-way dipole to hit the appropriate trajectories
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 26
Plans
• FY 13-15– Design and investigate the Accumulator and Compressor
Rings– Contribute to IDS-NF with Project X Proton Driver
information– Single beam line interface with Target Area for Neutrino
factory– Develop multi-beam lines and final focus magnet concepts
for Muon Collider– Develop MAP staging options with Proton X
• FY 16-18– Evaluate MAP staging options with Proton X– Prepare performance and costing for Technical Feasibility
ReportAugust 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 27
Back-up Slides
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 28
Project X Ion Source
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 29
Project X RFQ Studies
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 30
Project X CW Linac: Worst Case
• 3 GeV physics program stay with average beam current of 1 mA.– 10% at 5 mA and 90% at 1 mA average current
August 30, 2012
K. Gollwitzer | DOE Review of MAP (FNAL, August 29-31, 2012) 31
Project X 650 MHz RF Power
August 30, 2012